The first of three standardized field sobriety tests for operating while intoxicated investigations is called the Horizontal Gaze Nystagmus test. The majority of people charged with drunk driving present to the attorneys office claiming to have passed this test because as far as they were aware, they were able to properly follow the officers pen or finger throughout this test. Unfortunately, an individuals ability to follow the stimulus is not the primary concern of this test. While it is necessary to follow the stimulus for the officer to correctly administer and interpret the test results, the officer is looking for much more.
This test is designed to look for and detect the presence of Gaze Nystagmus in the human eye. "Nystagmus" although a complicated sounding word simply means the involuntary jerking of the eye. Nystagmus occurs in every human's eyes all the time however, it is not normally observable under normal circumstances. The theory underlying this test is that when someone has consumed excessive amounts of alcohol the "jerking" of the eye becomes more pronounced and sustained and is visible to another human eye when the eye is manipulated in various ways. This field sobriety test is the only field sobriety test that has any background in science of medicine. However, there are a number of different problems with the use of the Horizontal Gaze Nystagmus test in criminal prosecutions that should be noted.
First, there are over 45 different medically and legally recognized causes of conditions in the eye that can simulate Horizontal Gaze Nystagmus. Officers are not trained to detect and differentiate between Horizontal Gaze Nystagmus and any of the other conditions in the eye that may cause the eye to involuntarily twitch or jerk. Officers ARE trained however that different environmental factors can cause Nystagmus even absent the consumption of alcohol by the individual being tested. One such phenomenon is known as Optokinetic Nystagmus which can be caused by rotating lights or rapidly moving traffic in close proximity to the individual being tested. What is present in the majority of drunk driving arrests? That is correct, traffic passing in close proximity and police vehicles with their overhead rotating lights activated.
Second, a number of common prescription medications such as Cerebryx and Dilantin have Nystagmus listed as a potential side effect. It is important to notify your attorney if you were taking any prescription medications at the time of your arrest. You can also check for yourself at http://www.fda.gov/
Third, the large majority of all police officers do not administer the test correctly and fail to follow the standardized procedures and protocols. There are very specific standardized procedures and protocols for the administration of this test that must be followed for the test results to have any validity or reliability per the officers own training manuals. This author can count on one hand the number of Horizontal Gaze Nystagmus Tests that he has observed actually been conducted correctly.
Finally, there is no independent objective verification available in this type of test to determine whether or not the officer actually is observing Nystagmus as alleged. Officers will claim the individual scored 6 out of the 6 possible cues thus "failing" this test miserably. . . . prove him wrong. There is no video camera that is zoomed up into the tested person's eyes and whether or not Nystagmus is actually present can not be objectively challenged. Even the most talented DUI attorney is stuck attacking the manner in which the test is administered as opposed to showing a jury that the objective evidence establishes Nystagmus was not present. While this can an often times if very effective, there is no substitute for objective video evidence showing that what the officer claims to have observed was not present.
In conclusion, an individual submitting to the Horizontal Gaze Nystagmus test is completely at the mercy of the officer administering the test to administer and interpret the test correctly and truthfully. The officer already thinks that the test subject is potentially under the influence of alcohol which is why the test is being administered in the first place. Why put yourself in that precarious position when, in the State of Iowa, you have the absolute right to refuse field sobriety testing. You do not lose your driving privileges for refusing field sobriety testing. You may be arrested and taken to jail but chances are if you submit to these tests you will be arrested anyway. If you really think about it, you could take all the field sobriety tests, blow below the legal limit on the preliminary breath test, and still be arrested and taken to jail for the night. Know your rights, exercise your rights, preserve your freedom!